1. Field of the Invention
The present invention relates to a mobile communication terminal, and in particular to an automatic time setting method of an asynchronous mobile communication terminal.
2. Description of the Prior Art
In general, a synchronous mobile communication terminal operated in a CDMA (code division multiple access) network receives time information from a base station. On the contrary, an asynchronous mobile communication terminal (hereinafter, it is referred to as a terminal) operated in a GSM (global system for mobile communication) network and a GPRS (general packet radio service) network not only receives time information from a base station but also generates time information by using a RTC (real time clock) circuit disposed therein.
In more detail, in the terminal operated in the GSM/GPRS network, the RTC circuit counts a low frequency clock signal (32.768 KHz) and generates time information (second, minute, hour), and a CPU is synchronized with a high frequency clock signal (13 MHz) and displays time information generated in the RTC circuit on a LCD.
However, when a user travels a large number of countries operating the GSM/GPRS network, a time difference may occur between countries or cities. In that case, the user has to calculate a time difference between a previous area and a present area and input a present time manually by using a time setting menu of the terminal.
For example, when the user moves from Berlin (Germany) to London (England), the user has to calculate a time difference (−1) between Berlin and London and reset a present time (from a Berlin time to a London time) of the terminal by using a time setting menu of the terminal.
As described above, when the terminal user moves from a first area to a second area in the GSM/GPRS network, in the conventional art, because the user has to calculate personally a time difference between two areas and reset a time of the terminal in every case, it is intricate.